The proposed training program will provide postdoctoral trainees with a rigorous laboratory experience in molecular pathogenesis, emphasizing host-pathogen interactions. Training will be primarily laboratory based, but will also include a required semester course in host-parasite interactions taught by the training faculty. For MD trainees (estimated to be half) a laboratory practicum will precede their assignment to laboratories. Recent faculty recruitment efforts have resulted in the formation of a critical mass of established investigators in the broad area of microbial pathogenesis and accordingly this application proposes to establish an integrated training program for post doctoral trainees in host-pathogen interactions. In addition to their common research interests, many of these faculty already have evidence of collaborative interactions. Faculty research interests encompass areas that include regulation of virulence gene expression, host- pathogen interactions, molecular immunology and immune defense, molecular virology and bioinformatics. The program consists of 12 faculty, all of whom hold NIH grants and who, as a group, have had a substantial training history. As a whole, this group has earned national and international recognition in their respective fields. The training faculty represents a broad range of departmental affiliations, including the Departments of Medicine and Microbiology at Boston University School of Medicine, and the Division of Biomedical Engineering at Boston University. The major goal of the program will be to: 1) recruit and enroll trainees of the highest quality including underrepresented minorities; 2) provide these trainees with a multidisciplinary background in molecular pathogenesis coupled with intensive laboratory training in a focused project that examines a host-parasite interaction(s); 3) to teach trainees to think critically and to ask relevant and feasible research questions; 4) to instill these trainees with a sense of ethical behavior; 5) to help develop effective written and oral communication skills among the trainees; and 6) to facilitate collaborative interactions among both students and faculty of the host-pathogen interaction training Program.